LONDON (Reuters) - Lawyers for Brexit campaigner Arron Banks ordered the European Parliament’s chief Brexit coordinator on Wednesday to retract a claim that Banks colluded with Russia to deliver Britain’s vote to leave the European Union.

Guy Verhofstadt, who leads the European Parliament Brexit coordination team, said on Twitter on Wednesday that far-right and right wing leaders across Europe made up a fifth column of cheerleaders for Russian President Vladimir Putin.

In a letter to Verhofstadt, Bank’s lawyers, Mishcon de Reya, quoted the tweet which mentioned former UK Independence Party leader Nigel Farage as a cheerleader and said Banks “colluded w/ Russians to deliver #Brexit”.

“Anyone reading the tweet would be left in no doubt that it defames our client,” Mishcon de Reya said in the letter to Verhofstadt. “Please now delete the tweet and tweet a retraction.”

Banks said Verhofstadt’s remark was “an outrageous statement”.

“We are not funded by the Russians,” he told Reuters. “If he does not retract the statement, we will go ahead and sue him for defamation. So he can save himself a whole load of time and money and just retract it.”

Verhofstadt did not immediately reply to a request for comment made outside normal business hours.